Case 1850K Crawler Dozer Repair Manual

The Case 1850K crawler dozer is the flagship model of the K-Series lineup, designed for high-output earthmoving, land clearing, and construction projects. Featuring a powerful Cummins turbocharged diesel engine, hydrostatic dual-path transmission, and advanced load-sensing hydraulics, the 1850K delivers exceptional pushing power, fine control, and operator comfort. With operating weights ranging from 43,000 to 45,000 lb, it is built to handle large-scale dozing applications with efficiency and reliability.

Sect. 0 – Generalities
The 1850K is engineered for heavy-duty performance with robust construction, a reinforced undercarriage, and multiple configurations including XLT and LGP. Its operating weight and balance provide excellent traction and productivity across a variety of job site conditions.

Sect. 1 – Engine
Powered by a Cummins QSC8.3 six-cylinder turbocharged diesel engine with 8.3 L (504 cu in) displacement, the 1850K produces 205 gross horsepower (190 net) at 2,200 rpm. With peak torque of ~660 lb-ft at 1,400 rpm, it delivers the strength needed for demanding dozing and grading tasks while maintaining fuel efficiency.

Sect. 2 – Transmission
The machine features a dual-path hydrostatic drive system, providing infinite variable speed control and counter-rotation. Travel speeds reach up to 6 mph, allowing the dozer to maneuver efficiently while maintaining constant power to the tracks.

Sect. 3 – Final Drives
Heavy-duty planetary final drives are designed to handle high torque loads and ensure long-term reliability under continuous heavy pushing conditions.

Sect. 4 – Brakes and Steering
Dynamic hydrostatic braking is complemented by hydraulic wet-disc service brakes for dependable stopping power. Steering is precise and smooth, supported by hydrostatic control for tight turns and accurate grading.

Sect. 5 – Undercarriage
The undercarriage includes eight bottom rollers and two carrier rollers per side, with 44–46 track shoes depending on configuration. Track shoe widths range from 22 to 30 inches, offering ground pressures of 6.5 psi (XLT) to 5.0 psi (LGP), ensuring stability and traction in both firm and soft soil conditions.

Sect. 6 – Dozing Equipment Hydraulic System
The load-sensing hydraulic system features a variable-displacement piston pump delivering up to ~46 GPM at 3,000 psi. With a 29-gallon hydraulic reservoir, the system provides consistent and responsive blade control. The standard six-way PAT blade offers a capacity of 7.0 to 7.6 yd³, enabling efficient earthmoving operations.

Sect. 7 – Electrical System
The 1850K uses a 24-volt electrical system with dual 12V batteries and a 100-amp alternator. This setup ensures reliable starts and powers lighting, controls, and diagnostics.

Sect. 8 – Air Conditioning Unit
The ROPS/FOPS-certified cab can be fitted with heating and air conditioning systems, providing operator comfort in all working conditions. Wide visibility, ergonomic controls, and a low-noise environment increase productivity during long shifts.

Key Highlights

• Engine: Cummins QSC8.3, 6-cyl turbo diesel, 8.3 L, 205 gross HP / 190 net HP
• Max torque: ~660 lb-ft @ 1,400 rpm
• Operating weight: 43,000 – 45,000 lb
• Transmission: Hydrostatic dual-path drive, variable speed up to ~6 mph
• Hydraulics: Load-sensing piston pump, 46 GPM @ 3,000 psi, 29-gal reservoir
• Blade: Six-way PAT blade, 7.0 – 7.6 yd³ capacity
• Tracks: 8 bottom rollers, 2 carrier rollers, 22–30 in shoes, 44–46 shoes/side
• Ground pressure: 6.5 psi (XLT) to 5.0 psi (LGP)
• Fuel capacity: 90 gal; Hydraulic capacity: 29 gal
• Electrical: 24V system, dual 12V batteries, 100A alternator
• Cab: ROPS/FOPS with HVAC options for operator comfort